Schwartz, U.S. Pat. No. 3,845,241, entitled "Television Display Panel Having Gas Discharge Cathodo-Luminescent Elements" discloses a display panel that comprises a multitude of light-emissive elements arranged in a matrix across the faceplate of the panel. The elements are selectively ignited to display an image. The light-emissive elements include multiple rows of gas discharge cells that extend horizontally from one side of the panel to the other. The gas discharge cells are sealed against the faceplate. Vertically oriented phosphor strips are carried on the side of the faceplate that is near the gas discharge cells. The portion of each phosphor strip that extends across a cell defines a pixel.
Each gas discharge cell has a cathode at one end and several apart-spaced discharge anodes at the other end. Voltages are applied to the discharge anodes and cathode so that a potential difference is created that is great enough to ignite and sustain a gas discharge in a selected horizontal cell. The gas discharge provides a source of free electrons.
A control electrode grid is positioned near the phosphor strips and extends across all the gas discharge cells. A high-voltage acceleration anode covers the phosphor strips. The control electrode grid and acceleration anode control the free electron flow to the pixels to produce one horizontal line of an image.
After a suitable horizontal line display time, the gas discharge is commuted to an adjacent gas discharge cell. The resultant free electron flow is controlled to produce another line of the image. During each frame period, all of the horizontal rows of gas discharge cells are scanned in the manner just described to display a complete image on the faceplate.
Prior gas discharge cathodoluminescent devices of the type described above suffer from low pixel brightness because any given pixel is actuated for only a relatively short horizontal line time during one frame period. Specifically, a gas discharge is maintained in the scanned cell only during the horizontal line time. During the next line time, the gas discharge is ignited in the adjacent row and the gas discharge in the prior row is extinguished. Therefore, for an exemplary 250 horizontal line display using noninterlaced vertical scanning, the duty cycle of any pixel is 1/250 or 0.4% for each frame.
It can be appreciated that if the per-frame pixel duty cycle were increased, greater brightness would be achieved as a result of the correspondingly increased current applied to the pixels.